> ## Documentation Index
> Fetch the complete documentation index at: https://docs.newly.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Build your first app

> Go from signing in to your first app running in a cloud simulator.

This guide takes you from signing in to Newly v2, at app.newly.app and in Newly for Mac, to your first app running in a cloud simulator.

## Before you start

* **A browser or a Mac.** The web app at app.newly.app needs nothing installed. Newly for Mac needs a Mac with Apple silicon and macOS 14 or later. See [The web app and Newly for Mac](/get-started/web-and-mac).
* **A plan, or credits from Newly.** Newly v2 has no free credits at sign-up. You can't create a project or run a Newly Agent prompt with 0 credits unless Newly gives you credits or a gift plan. You pick a plan in step 4.

<Note>
  You don't need a phone or Xcode to build and try your app. It runs on cloud simulators inside Newly.
</Note>

## Build your first app

<Steps>
  <Step title="Open Newly">
    Go to app.newly.app in your browser, or download Newly for Mac from newly.app/download and open it.
  </Step>

  <Step title="Sign in and answer a few questions">
    Sign in with an email code, Google or GitHub. See [Sign up and sign in](/get-started/sign-in).

    The first time you sign in, Newly asks a few short questions, such as "How did you hear about us?" and "How much of this have you done before?". A three-card tour follows. Press **Start building** on the last card.

    On Mac: after the tour, the Mac app may offer to set up local development, which installs Xcode and the iOS Simulator. You don't need this for your first app. Choose **Set this up later** to skip it.
  </Step>

  <Step title="Describe your app on Home">
    Home shows a prompt box under "Let’s make something new". Describe the app you want in a few sentences: who it's for, the main screen, and what someone does there.

    On Mac: under the prompt box, pick **Remote** in the menu for your first app. A Remote chat runs in the cloud and works the same as the web app, with no Xcode needed. In the web app, every chat is Remote, so there's nothing to pick.

    To copy the look of an existing site, paste a link to a public website into your prompt.

    Send the prompt. Newly creates a project, names it from the first line of your prompt, and starts a chat in it.
  </Step>

  <Step title="Pick a plan if Newly asks">
    If your account has no credits, sending your first prompt opens **Billing** with "Pick a plan to start building with Newly." Choose a plan and finish checkout, then send your prompt. No project is created until you have credits.

    If Newly sent you a gift link, open it in your browser before you pick a plan. See [Plans and top-ups](/billing/plans-and-top-ups).

    If you're a member of someone else's organization, only an owner or admin can buy credits. Ask them to add a plan.
  </Step>

  <Step title="Watch the agent work">
    Newly Agent builds a small first version on purpose: usually one screen with sample data. That gets something running quickly, and you shape it from there.

    The status line shows what the agent is doing, such as building the app or checking the preview. While the agent works, the send button turns into a stop button. After about 10 seconds the status line adds "You can stop safely: completed work stays saved."
  </Step>

  <Step title="See your app">
    Press **Preview** in the chat's title row. This opens the preview pane and starts your simulator when a build is ready. You can also press **Start my simulator** in the preview pane. Your app opens on a cloud simulator that you can tap and scroll like a phone.

    See [Previewing your app](/preview/overview) for the iOS, Android and Web views.
  </Step>

  <Step title="Keep improving it">
    Ask for one change at a time, then check the result in the preview. For example: "Add a settings screen with a dark mode switch."

    * To talk through an idea without changing code, switch the prompt box to **Ask** or **Plan**.
    * If a change goes wrong, use **Restore to here** on an earlier message to go back. See [Undo and Restore to here](/code/undo-and-restore).
  </Step>
</Steps>

## What uses credits

Newly Agent's work in your chat uses credits. Watching your app in a cloud simulator doesn't draw down credits. See [How credits work](/billing/how-credits-work) for the full list.

## Next steps

<CardGroup cols={2}>
  <Card title="How credits work" icon="coins" href="/billing/how-credits-work">
    What uses credits and how plans refill them.
  </Card>

  <Card title="Previewing your app" icon="eye" href="/preview/overview">
    Cloud simulators, the Web view and the preview pane.
  </Card>

  <Card title="Testing on a real phone" icon="mobile" href="/preview/test-on-a-phone">
    Try your app on your own iPhone.
  </Card>

  <Card title="Ship your iOS app to TestFlight" icon="paper-plane" href="/publish/testflight">
    Owners and admins can send an iPhone build to TestFlight from a Remote chat.
  </Card>
</CardGroup>